Southwest Airlines’ (SWA) smooth path to integrating with AirTran Airways, which it acquired last year, hit some turbulence with Tuesday’s rejection by the carrier’s 1,600 mechanics of a seniority integration agreement.

The Aircraft Mechanics Fraternal Assn. (AMFA) Local 11 had reached an accord with SWA and AirTran’s 400 mechanics, but the members have voted to reject it, taking a different track from flight attendants and pilots who have approved integration pacts ( ATW Daily News, Nov. 9, 2011 ).

“Our goal continues to be the speedy resolution of seniority integration,” SWA VP-maintenance operations Jim Sokol said in a statement. The airline said the next step was to file for arbitration, but added that it remained open to working toward a negotiated solution.

SWA and AirTran expect to receive a single operating certificate from FAA next month.